An electromagnetic actuator obtained by molding a bobbin around which a coil is wound and a stator with a molding resin is known (for example, U.S. Pat. No. 6,688,334B2).
The bobbin and the stator are assembled at the time of molding a bobbin and a stator. The bobbin and the stator are positioned by fitting a positioning projection provided on a bobbin flange to a positioning hole formed in a stator flange as positioning means.
In the stator flange, a resin-passing hole for passing a molding resin has to be formed. A plurality of resin passing holes are formed in positions extending radially from the center of the stator flange to prevent occurrence of poor molding.
In the conventional art, the positioning holes are closed with the positioning projections. Consequently, poor molding has to be prevented by forming the plurality of resin passing holes, and many resin passage holes are necessary.
The stator flange is a part through which magnetic flux passes. When the number of resin passing holes is large, the amount of magnetic flux passing through the stator flange decreases. In particular, when the electromagnetic actuator is miniaturized, the sectional area of a magnetic circuit becomes insufficient due to the many resin-passing holes, and it disturbs miniaturization of the electromagnetic actuator.
The flow of the molding resin has to be made uniform in the whole periphery so as to prevent poor molding. In the conventional art, however, the molding resin does not flow smoothly in the positioning means (the fitting portion between the positioning holes and the positioning projections) of the bobbin and the stator, so that the flow of the molding resin cannot be made uniform in the whole periphery, and poor molding tends to occur.